Cistanche

Cistanche
File:Broomrape (Cistanche tubulosa) Negev.jpg
Cistanche tubulosa
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Asterids
Order:	Lamiales
Family:	Orobanchaceae
Genus:	Cistanche
Species
Cistanche ambigua Cistanche deserticola Cistanche phelypaea Cistanche salsa Cistanche sinensis Cistanche tubulosa others

Cistanche is a worldwide genus of holoparasitic desert plants in the family Orobanchaceae. They lack chlorophyll and obtain nutrients and water from the host plants whose roots they parasitize.

Uses

Along with other members of the genus, Cistanche deserticola is the primary source of the Chinese herbal medicine cistanche (Chinese: 肉苁蓉, pinyin ròucōngróng). The main sources of cistanche are Cistanche salsa and Cistanche deserticola, although it may also be obtained from Cistanche tubulosa, Cistanche sinensis, and Cistanche ambigua. The drug, known in Chinese as suosuo dayun, is collected in spring before sprouting, by slicing the stems of the plant. Cistanche deserticola has been placed on CITES Appendix 2, a list of endangered species not banned from trade but requiring monitoring. With increased consumption of cistanche, the population of the species has decreased and its area of distribution has shrunk. Aside from over-collection or indiscriminate collection, an important factor in the diminished supply of cistanche is a loss of the saxaul host, Haloxylon ammodendron, which is widely used for firewood.

Cistanche has been used as a medicine for about 1800 years and is recorded in the Shennong Bencao Jing and Bencao Gangmu as a tonic. Most of the medicinal claims have never been evaluated through clinical testing, and those claims that have been examined under controlled medical study are not supported.

Growth

Growing in arid climates, cistanche is a parasitic plant that connects to the conductive system of a host, extracting water and nutrients from the roots of the host plant. Cistanche is native to the Taklimakan desert region of Xinjiang Uyghur Autonomous Region northwest China where it grows on host desert plants tamarix and haloxylon ammodendron.

Research in laboratory animals

A variety of pharmacological effects of extracts or chemical compounds isolated from different species of Cistanche have been reported in in vitro studies or in rodent models. The chemical constituents which may be responsible for these effects include acteoside, echinacoside, and cistanosides (A, B, C, D, E, F, G and H). These effects have not been demonstrated in humans.

Some of these effects include:

• Cistanche tubulosa extract "exhibits hypocholesterolemic activity in diet-induced hypercholesterolemia mice."
• Polysaccharides isolated from Cistanche deserticola have in vitro immunomodulatory effects in high doses, "promoting the phagocytic and secretory functions of the phagocytic ability of peritoneal macrophage".
• Cistanche salsa extracts enhance antibody production in isolated human lymph node lymphocytes in vitro.
• High doses of the chemical compound acteoside, isolated from Cistanche tubulosa, affected biomarkers related to aging in mice.
• Anti-fatigue properties have been shown in mice. Cistanche deserticola extracts "appeared to enhance the swimming capacity of mice by decreasing muscle damage, delaying the accumulation of lactic acid and by improving the energy storage."
• A laboratory study in mice found that high doses of Cistanches Herba extract (CHE) "significantly enhanced learning and memory, as demonstrated by passive avoidance test and novel object recognition test". These results were determined to be the result of its action in upregulating nerve growth factor.